Core Idea
Definition
Case-based reasoning draws on stored examples, precedents, or prior episodes to guide action in a new but similar situation.
In Plain English
When facing a new problem, you ask, what have we seen before that is close enough to teach us something useful?
Framework Structure
Components
Flow
Define current case -> Retrieve similar cases -> Compare similarities and differences -> Adapt prior solution
How to Apply
- 1.Describe the current problem in enough detail to compare it properly
- 2.Retrieve several past cases rather than only the most memorable one
- 3.Check which features are genuinely similar and which are not
- 4.Adapt the old response to the current constraints instead of copying it blindly
- 5.Record the new case so it improves future judgment
When to Use
- •Operations, support, or incident handling
- •Negotiation and management situations with recurring patterns
- •Product or go-to-market decisions with useful precedents
- •Training novices using worked examples
- •Any environment where past cases are plentiful and informative
When NOT to Use
- •When the situation is genuinely novel in the variables that matter most
- •When precedent is low quality or outdated
- •When copy-pasting the old solution would ignore changed constraints
- •When a more formal causal or quantitative method is necessary
Example
Problem
A customer success lead must respond to a renewal risk with a strategic account.
Application
- 1.Describe the current situation: product usage drop, budget pressure, executive change
- 2.Review prior renewal-risk cases with similar warning signs
- 3.Compare which interventions worked under similar constraints and which failed
- 4.Adapt the best prior playbook to the current customer rather than reusing it unchanged
Conclusion
The lead chooses a tailored rescue plan informed by precedent but adjusted for the new executive context.
Takeaway
Past cases are most useful when they function as structured memory, not as scripts.
Common Mistakes
- •Picking the nearest case emotionally rather than structurally
- •Forgetting the context that made the old solution work
- •Ignoring base rates because one precedent feels compelling
- •Treating precedent as authority instead of evidence
- •Failing to store and review outcomes from adapted cases
How to Practice
precedent log
Keep a compact log of important cases, the intervention used, and the outcome.
similarity score
Before reusing a precedent, score how similar the old and new cases are on the variables that matter most.
adapt not copy
When using a past case, explicitly write what you will keep, modify, and discard.
Related Cognitive Biases
availability bias
The easiest case to remember is not always the most relevant one.
recency bias
Recent cases can overshadow better but older precedents.
representativeness bias
Surface similarity can make a weak precedent feel stronger than it is.
Related Frameworks
Related Skills
Variants & Extensions
Typical Failure Modes
- •Weak precedent match
- •Blind copying
- •Overweighting memorable cases
Further Reading
- Sources of Power by Gary Klein
- How Doctors Think by Jerome Groopman
- The Checklist Manifesto by Atul Gawande